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The DXF file format was created by Autodesk in 1982 and the intention was to create a format that was independent of CAD applications and therefore eased the difficulties of sharing files created by different applications. This was particularly important for early versions of CAD as reverse engineering of the closely guarded DWG format was limited. However in recent years the usefulness of DXF format has reduced due to DXF not being able to support more advanced CAD elements such as dynamic blocks. The market leading popularity of AutoCAD has also reduced the requirement for an application independent format.

DXF files are organised in way that allows the files to be opened by a normal text editor application.vA DXF file has a common format containing a number of sections. These include the Header which contains file property information, Classes, Tables, Entities, Blocks and Thumbnail Image section. The data contained within a DXF is known as tagged data which means that the tags identify how the data should be interpreted. For example there are a large number of group codes related to the creation of an ellipse. Various group codes allow for the definition of the start and end points, centre point and extrusion directions.

Tiff was originally created by a company called Aldus, and is now owned by Adobe systems, it is a file format for storing images, including line art and photographs. It was created due to the popularity of scanners and was thought-up to become the standard scanned image file format. It is a popular format for high-colour-depth images and it has also been adapted to accommodate greyscale images.

A TIFF file is made up of many different blocks which define the palette data or the LZW-compressed body among other things. The byte order is either Motorola or Intel depending on the first word. if it is MM, then you have Motorola byte ordering and likewise if it is II it means you have Intel byte ordering. Each TIFF file begins with an image file header which then points to an image file directory which contains the image data and image information.